Tribological Studies on Zinc Aluminum Cast Alloys

Abstract

Materials has important role in the design and development of engineering appli-cations. The material selection is based on many parameters like structural, physical, electrical and thermal properties. Designers try the best products based on their experi-ence where material is the key parameter. Continuous research is going on for centuries based on the requirements. Mechanical industry where structures/machines are heavy in size requires huge materials for fabrication. But with the advances in the material and manufacturing technologies, the human quest for lean manufacturing is more and the best materials are used based on the uniform stress concept and its allowable ranges. Copper-based alloys such as tin bronzes and leaded bronzes have always been used with cast bearings. However, copper, tin and lead have been declared as scare mate-rials by many countries. But with the development of heavy machinery, the focus is oriented towards the development of high strength materials especially towards bearing applications. newlineZinc-based alloys are the traditional materials used by humans for general applica-tions. Zinc alloys have the advantage of easier castability along with higher mechanical properties. In the past decade, most of the researchers concentrated their work on alu-minum alloys due to its higher strength to weight ratio along with good thermal and electrical properties. But the weakness of aluminum under high temperature conditions for dimensional stability along with higher wear rate made the researchers to look for better materials which can maintain higher dimensional stability under heavy loading and thermal conditions. newlineIn the present work, modified Zinc Aluminium (ZA)-27 alloys were developed based on the shortfalls of aluminum alloys. But even Zinc-based alloys have the sus-ceptibility of loss of strength and hardness which are very important parameters for bearing applications at elevated temperatures. Nickel was found to be an alternative for solving these problems. By the addition of nickel as re